1. Field of the Invention
The present invention relates to an electronic machine having a slot for mounting a dismountable card therein. More particularly, the present invention relates to a card slot apparatus having an improved structure for easy mounting of the card, and an electronic machine having the same.
2. Description of the Related Art
An integrated circuit (IC) card (referred to as a card below), such as a personal computer memory card international association (PCMCIA) card, is mountable in a card slot apparatus in an electronic machine, such as a lap top computer or a slim digital television, for use therein. When the card is inserted in the card slot apparatus, it is electrically connected to the electronic machine to carry out a desired operation.
Recently, such cards are tending toward increased high level functionality and integration of circuit chips in a large scale. Accordingly, during operation, the card radiates a large amount of heat. Because the heat radiated during the operation of the card may increase temperature in the card, which can result in abnormal operation of the card, it is necessary for the card slot apparatus to be equipped with a heat radiating unit.
An example of a card slot apparatus having a heat radiating unit is disclosed in a Japanese patent publication No. H10-198462. FIG. 1 is a view schematically illustrating the card slot apparatus disclosed in the Japanese patent publication No. H10-198462.
As illustrated in the drawing, the card slot apparatus has a heat radiating unit 20 installed in a slot. When a card C is inserted in the slot, the heat radiating unit 20 comes in contact with the card C and radiates heat generating from the card C.
However, according to the card slot apparatus as described above, when the card is inserted in the slot, the heat radiating unit 20 and the card C come in contact with each other. Accordingly, a problem may occur in that it is difficult to insert and eject the card into and from the slot, and a surface of the card can be scratched.
To address the problem, a structure that shelters a heat radiating unit (that is, a heat sink) in an upper part of a slot before the card is inserted has been proposed and disclosed in a Japanese patent publication No. 2005-222537. When the card is inserted in the slot, the heat radiating unit gradually goes down by a cam unit and comes in contact with the card.
The card slot apparatus (Japanese patent publication No. 2005-222537) as described above presents a problem in that at an early stage of inserting the card, the card and the heat radiating unit do not contact each other, thereby allowing the card to be easily inserted. However, from a certain point of time, the card and heat radiating unit contact each other, thereby resulting in an increase in insertion resistance of the card. Even though the card is not completely connected with an electronic machine, some users may determine that the card is completely inserted and quit the inserting operation of the card, due to the increased insertion resistance of the card. As a result, a connection error of the card may occur.
Also, a technique that lowers a heat radiating unit using a cam unit like the Japanese patent publication No. 2005-222537 has been proposed and disclosed in a Japanese patent publication No. 2005-285522. In the Japanese patent publication No. 2005-285522, a structure that automatically lowers the heat radiating unit after a card is completely inserted is employed. According to the structure, because the heat radiating unit and the card do not contact each other while the card is inserted, there is almost no insertion resistance of the card. However, a unit is required to independently lower the heat radiating unit after the card is completely inserted. Accordingly, a problem may occur in that such structure is complicated or the number of parts is increased, thereby increasing mechanical troubles and fabrication costs.
Accordingly, a need exists for a card slot apparatus having an improved heat radiating unit that is movable in response to insertion and removal of a card.